Thanks everyone.

Nala plays the most. Simba likes to play with Nala, Kiara likes to play with Nala. So when they both want to play, Nala has to defend herself against the two of them.

Nala weighs 58
Kiara weighs 40
Simba is probably in the 40's-50's, his vet appointment is coming soon so we'll know then for sure